Acute cardiovascular effects of bitter orange extract (p-synephrine) consumed alone and in combination with caffeine in human subjects: A placebo-controlled, double-blind study.
Nicholas A RatamessJill A BushSidney J StohsNicole L EllisIra T VoughtElizabeth A O'GradyJeremy D KuperSaif B HasanJie KangAvery D FaigenbaumPublished in: Phytotherapy research : PTR (2017)
The purpose was to examine cardiovascular responses to supplementation with p-synephrine alone and in combination with caffeine during quiet sitting. Sixteen subjects were given (in double-blind manner) either 103 mg of p-synephrine (S), 233 mg of caffeine +104 mg of p-synephrine (LC + S), 240 mg of caffeine (LC), 337 mg of caffeine +46 mg of p-synephrine (HC + S), 325 mg of caffeine (HC), or a placebo. The subjects sat quietly for 3 hr while heart rate (HR) and blood pressure were measured. Only HC + S and HC significantly increased mean systolic blood pressure (SBP) during the second hour and tended to increase mean SBP during the third hour. Mean diastolic blood pressure in S was significantly lower than the other trials during the first and second hours, and mean arterial pressure was significantly lower in S compared to the LC, LC + S, HC, and HC + S trials. No differences were observed in HR. Consumption of p-synephrine may acutely reduce diastolic blood pressure and mean arterial pressure and not affect SBP or HR during quiet sitting. The addition of p-synephrine to caffeine did not augment SBP or HR indicating that consumption of up to 104 mg of p-synephrine does not induce cardiovascular stress during quiet sitting.
Keyphrases
- blood pressure
- heart rate
- hypertensive patients
- double blind
- placebo controlled
- heart rate variability
- simultaneous determination
- clinical trial
- left ventricular
- mass spectrometry
- randomized controlled trial
- squamous cell carcinoma
- blood glucose
- oxidative stress
- study protocol
- solid phase extraction
- anti inflammatory
- liver failure
- high resolution
- atrial fibrillation
- ejection fraction
- stress induced